Datasheet LTC2493 (Analog Devices)

LTC2493 24-Bit 2-/4-Channel ∆∑ ADC with Easy Drive Input Current Cancellation and I2C Interface
FeaTures DescripTion
n
Up to 2 Differential or 4 Single-Ended Inputs
The LTC®2493 is a 4-channel (2-channel differential), 24-bit, n
Easy Drive™ Technology Enables Rail-to-Rail
No Latency ∆∑™ ADC with Easy Drive technology and a
Inputs with Zero Differential Input Current
2-wire, I2C interface. The patented sampling scheme elimi- n
Directly Digitizes High Impedance Sensors with
nates dynamic input current errors and the shortcomings
Full Accuracy
of on-chip buffering through automatic cancellation of n
2-Wire I2C Interface with 9 Addresses Plus One
differential input current. This allows large external source
Global Address for Synchronization
impedances and rail-to-rail input signals to be directly digi- n
600nV RMS Noise
tized while maintaining exceptional DC accuracy. n
Integrated High Accuracy Temperature Sensor
The LTC2493 includes a high accuracy temperature n
GND to VCC Input/Reference Common Mode Range
sensor and an integrated oscillator. This device can be n Programmable 50Hz, 60Hz or Simultaneous configured to measure an external signal (from combi- 50Hz/60Hz Rejection Mode nations of 4 analog input channels operating in single- n 2ppm INL, No Missing Codes ended or differential modes) or its internal temperature n 1ppm Offset and 15ppm Full-Scale Error sensor. The integrated temperature sensor offers 1/30th °C n 2× Speed/Reduced Power Mode (15Hz Using Internal resolution and 2°C absolute accuracy. Oscillator and 80µA at 7.5Hz Output) n No Latency: Digital Filter Settles in a Single Cycle, The LTC2493 allows a wide common mode input range Even After a New Channel Is Selected (0V to VCC), independent of the reference voltage. Any n Single Supply 2.7V to 5.5V Operation (0.8mW) combination of single-ended or differential inputs can n Internal Oscillator be selected and the first conversion, after a new channel n Tiny 4mm × 3mm DFN Package is selected, is valid. Access to the multiplexer output en- ables optional external amplifiers to be shared between all
applicaTions
analog inputs and auto-calibration continuously removes their associated offset and drift. n Direct Sensor Digitizer n Direct Temperature Measurement L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and No Latency ∆∑ and Easy Drive are trademarks of Linear Technology Corporation. All other n Instrumentation trademarks are the property of their respective owners. n Industrial Process Control
Typical applicaTion Data Acquisition System with Temperature Compensation Integrated High Performance Temperature Sensor
2.7V TO 5.5V 5 4 10µF CH0 V 0.1µF CC 3 CH1 2 REF+ 1.7k 1 IN+ 4-CHANNEL 24-BIT ∆∑ ADC SDA 0 MUX 2-WIRE WITH EASY-DRIVE SCL I2C INTERFACE CH2 –1 IN– CH3 REF– –2 CA1 ABSOLUTE ERROR (°C) COM 9-PIN SELECTABLE CA0 ADDRESSES –3 f –4 TEMPERATURE O SENSOR OSC –5–55 –30 –5 20 45 70 95 120 2493 vTA01a TEMPERATURE (°C) 2493 TA02 2493fe For more information www.linear.com/LTC2493 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics (Normal Speed) Electrical Characteristics (2x Speed) Converter Characteristics Analog Input and Reference I2C Inputs and Digital Outputs Power Requirements Digital Inputs and Digital Outputs I2C Timing Characteristics Typical Performance Characteristics Pin Functions Functional Block Diagram Applications Information Package Description Revision History Typical Application Related Parts